Chemical reaction

A team in which there is chemical change occur in substance. In a chemical reaction, one or more new chemical substance are formed from the original substance. Energy is either absorbed or released during chemical reactions. Chemical reactions occur at different speeds. Some reactions are very fast and some are very slow. As we know that their will be energy released or absorbed during reactions, on this basis reactions are divided into 3 groups

(1)Exothermic reaction: In these reaction heat is released. All combustion reaction are exothermic reaction. For eg.

CH 4 + 2O 2 -> CO 2H 2 O + heat

(2) Endothermic reaction: In these reaction energy is absorbed

Eg. N 2+ O 2+  heat -> 2 NO

(3) Photochemical reaction: The reaction which take place only when light is present. Eg. Photosynthesis

Some other type of reaction

Decomposition reaction: The reaction in which substance decompose on heating. eg.

2HgO -> 2 Hg + O 2

Combination or addition reaction: when molecules combine to forms a large molecules

Eg. 2 Mg + O 2 -> 2MgO

Displacement reaction: The reaction in which one element of a compound replace by another one.

Eg.  Fe + CuSO 4 -> FeSO 4 + Cu

Disproportional reaction: A chemical reaction In which only one substance vet oxidized as well as reduced is known as disproportional reaction

Eg. P 4 + NaOH + 2H 2 O -> 2 NaH 2 PO 2 + PH  3 here Phosphorus is oxidized as well as reduced.

Double displacement reaction: In a reaction where two compound react to form two different compound by mutual exchange ion. Eg.

AgNO 3 +NaCl -> NaNO 3 + AgCl

Neutralization reaction: A type of double decomposition when an acid reacts with base and form salt and water.

NaOH + HCl -> NaCl + H2

Reversible reaction: A reaction which can occur in both directions

Irreversible reaction: A reaction which cannot occur in both directions.



The number of moles of substance dissolved in litre of the solution

Acid and Bases

Acids : It is a substance which ionized in water to give H + ions. for eg. Hydrochloric acid ionized in water to give H + ions

HCl -> H+  +OH

Type of Acids

There are two type of acid (1) strong acid (2) weak acid

  1. Strong acid : An acid which is completely ionized in water and produce a large number of H + ions. Eg. HCl, sulphuric acid etc
  2. Weak acid: Acid which is partly ionized in water eg. Carbonic acid, acetic acid etc.

 Properties of Acid

  1. It changes the color of blue litmus to red
  2.  It is sour in taste
  3.  It reacts with carbonate to produce carbon dioxide gas
  4. If react with bases to neutralization.


A base is a substance which react with an acid to form salt. Bases are Proton acceptor. They contain oxide ions or OH - ions. A base is a substance which dissolves in water to give OH ions

Bases are of two type:

  1. Strong base: they gives large number of OH ions. Eg. NaOH, KOH etc.
  2. Weak base : they gives small number of OH ions. Eg. CaOH

Properties of bases:

  1. It changes the color of red litmus to blue.
  2. It is bitter in taste
  3. It reacts with acid to neutralization

pH scale

pH scale is a positive logarithm of Hydrogen ion concentration in moles per litre.

Washing soda

Chemical name of Washing soda is Sodium carbonate with 10moles of wager. It’s chemically formula is Na 2 CO 3 . 10 H 2 O

Uses of washing soda

  1. It is used as a cleaning agent for domestic purpose.
  2. Used for softening hard water
  3. It is used to manufacture of many useful sodium compound like caustic soda, borax, glass ,soap etc.
  4. Used as laboratory reagents

Baking soda

Its chemical name is Sodium bicarbonate and its chemical formula is NaHCO 3 .


  1. It is used as antacids in medicine to remove acidity
  2. It is used to make baking powder

Bleaching powder

Chemical name of bleaching powder is Calcium Oxychloride and its formula is CaOCl 2

Manufacturing of bleaching powder: It is manufactured by passing chlorine gas over dry slaked lime.


  1. It is used in textile industry, paper industry etc.
  2. It is used for bleaching washed cloth.
  3. It is used for making drinking water free from germs.
  4. It is used to form chloroform
  5. It is used as oxidizing agent

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Current affairs 05/06/2019

1). Comptroller and auditor general Rajiv Mehrishi has been appointed as the external auditors of World Health Organisation (WHO) for a four year term from 2020-23. 2).World Environment Day is observed on 5 June(Theme: The Air Pollution). 3). Madhya Pradesh cabinet has passed a resolution to increase reservation of OBC's 27%.

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करंट अफेयर्स 03-04/06/2019

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Current affairs 03-04/06/2019

1. Nyaib Bukele has been Sworn in as the president of  EI Salvador ( EI Salvador's capital: San Salvador, currency: United States Dollar). 2. National Security Advisor (NSA) Ajit Doval reappointed to his post and given Cabinet rank in the second term of the NDA government. 3. World Bicycle Day is observed on 3rd June .

Current Affairs Quiz

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डेली जीके क्विज 17/05/2019

1. भारतीय नौसेना प्रमुख का नाम बताएं? 2. हाल ही में ICC द्वारा पहली महिला मैच रेफरी के रूप में किसे नियुक्त किया गया है? 3. हाल ही में एक हल्के खेल विमान (एलएसए) में अटलांटिक महासागर को पार करने वाली दुनिया की पहली महिला कौन बनी है?

Daily Gk Quiz 17/05/2019
Daily Gk Quiz 17/05/2019

1. Name the Indian Navy Chief? 2. Recently who has been appointed as first female match referee by ICC? 3. Recently who has becomes the world’s first woman to cross the Atlantic Ocean solo in a light sports aircraft (LSA)?

डेली जीके क्विज 29/09/2018
डेली जीके क्विज 29/09/2018

प्रश्न 1)। हाल ही में एशियाई विकास बैंक (एडीबी) ने राज्य में रोजगार को बढ़ावा देने के लिए मध्य प्रदेश में पहला बहु-कौशल पार्क स्थापित करने के लिए 150 मिलियन डॉलर के ऋण को मंजूरी दे दी है। एडीबी के अध्यक्ष कौन हैं? प्रश्न 2)। परकर्म परव किस अवसर पर मनाया जा रहा है? प्रश्न 3)। भारत की लाइव स्टॉक जनगणना 1 अक्टूबर से शुरू होने वाली है। इस तरह की कितनी जनगणना पहले आयोजित की गई है और यह कौन सी जनगणना है?